Evaporator for refrigeration systems



v A. E. SCHNEIDER 4EVMORIJI0R FOR REFRIGERATION SYSTEMS v Filed Sept. 19, 1932 June `9, 1936.

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rr rie e r r r r r r t r r Patented June 9, 1936 y UNITED sTATEs EVAPORATOR FOR REFRIGERATION SYSTEMS Albert E. Schneider, Carter Lake, Iowa, assignor to Baker Ice Machine Co. Inc., Omaha, Nebr., a v corporation of Nebraska Application September 19, 1932, Serial N o. 633,710

4 Claims.

This invention relates 4to evaporators for refrigeration systems of the type described in my co-pending application filed June 26, 1929, Serial No. 373,836, and has for its principal object 5 to provide a simpler and more inexpensive con# struction wherein the refrigerant is free to move in all directions to eliminate the formation of gas pockets, thereby producing a uniform temperature over the entire surface of the evaporator, as Well as eliminating surging effects of the refrigerant.

It is a further object of the invention to provide for ready passage of oil from the evaporator.

l5 Another important object is'to provide a construction which may be readily galvanized or plated to prevent corrosion.

In accomplishing these and other objects of theV invention, I have provided improved details of structure, the Apreferred form of which is illustrated in the accompanying drawing, wherein:

Fig. 1 is a side elevational view of an evaporator constructed in accordance with my in-` vention.

Fig. 2 is an enlarged vertical sectional view through the evaporator showing the plate construction and the method of connecting the plates together to provide intercommunicating refrigerant channels.

Fig. 3 is a horizontal sectional view through the manifold on the line 3 3, Fig. 2, showing the inlet and outlet connections. i

Fig. 4 is a horizontal sectional view on the line 4-4, Fig. 2.

Fig. 5 is an enlarged perspective viewv of a part of the evaporator showing one of the connections.

Referring more in detail'to the drawing:

I and 2 designate the side plates of the evaporator and 3 the manifold or header for distributing refrigerant across the width thereof. The side plate I is preferably rectangular in shape and includes a flat metal sheet having a semi-circular portion 4 along its upper edge to cooperate with a similar portion on the other sheet as'later described to provide the header. I'he side plate 2 is of the same dimensions as the plate I, but is provided with a plurality of rows of spaced bosses 5 stamped therefrom to 5 form interconnecting, horizontally and vertically arranged channels 6 and 1, respectively, when the plates are placed together as shown in Fig. 2. The side and lower end margins of the plate are offset forwardly to a depth equal to the depth of the bosses and then laterally to provide side and end flanges 8, 9- and IIJ, respectively arranged to lie flat against the corresponding side and end edges of the plate I. The upper edge of the plate 2 is also provided with a semi-cylindrical portion I I which lies in juxtaposition with 5 the semi-cylindrical portion 4 of the plate I to form a cylindrical manifold having communication with the vertical channels 'I so the refrigerant may flow therethrough to ll the channels between the plates, as` later described. l0

In assembling the plates they are placed in vjuxtaposition with the side and end flanges of the plate 2 lying flat against the face of the plate and their side and end edges in registry with one another. 'Ihe edges are then welded 15 or otherwise secured together, as at I2 to provide a leak-proof joint. A row of rivets, as indicated at I3, may also be'inserted through the plates adjacent the opposite sides of the flanges to supplement the weld. Y 2( In ,order to tie the plates together intermediate their side edges to prevent spreading under pressure, the center of each of the instruck bosses is provided with a rivet opening I4 aligning with similar openings I5 in the opposite plate 25 to accommodate rivets I6 or other suitable fasteningdevices. If desired, the plates may be spot-welded together at these points to eliminate the rivets.

' 'Ihe abutting edges of the semi-cylindrical por- 30 tions of the plates are also Welded, as at I1, to complete the manifold. To reinforce the ends of the manifold it is internally threaded, as at I8. and provided with nipples I9 and 20, one of which may be connected to the refrigerantsup- 35 ply and the otherto the return line of a compressor as in customary practice.

The operation of a plate evaporator constructed and assembled as described is as follows:

The refrigerant is admitted through the inlet 40 of the manifold and after entering the header immediately gravitates to the bottom of the plate evaporator and gradually lls the spaces between' the plates until it reaches the height of the manifold bottom, at which time the outlet be- 45 comes chilled and shuts off the expansion valve by use of a thermo bulb clamped on the suction line (not shown), as in ordinary practice. The evaporator thus remains full of liquid at all times, thereby affording refrigerant liquid 50 contact with the vaporizing surfaces of the plates.

`This is a very limportant feature when sulphur dioxide is used as the refrigerant. The oil in the system, being of lighter specific gravity, floats on top of the refrigerant, and is forced back to lili the compressor through the suction line, thereby preventing the compressor from becoming dry due to the lack of lubrication.

The intersecting channels formed by the bosses afford ow for the refrigerant in al1-directions so that no gas pocket can be formed and the refrigerant moves freely in all directions to maintain a very uniform temperature upon the entire surface of the evaporator.

Evaporators of the type illustrated are readily adaptable to square compartments and may be of various dimensions to conform to the size of the compartment to be refrigerated.

The riveted and welded construction, reinforced by the stift'ening effect of the bosses, affords suillcient strength to withstand all practical v pressures.

Attention is directed to the fact that the channels provided by the bosses do not define definite paths for the refrigerant but it is free to flow in any direction in and around the bosses. This arrangement does not unduly limit the capacity of the channels, but provides a maximum capacity proportionate to the total surface of the evaporator since the prime surface is greatly in excess of the secondary or welded and riveted surfaces.

What I claim and desire to secure by Letters Patent is:

1. An evaporator including a substantially flat rectangular plate member having a plurality of spaced rows of bosses stamped from the body portion thereof and having outset marginal flanges extending along the sides and bottom edges of the plate member, a complementary at plate member flatly engaging said bosses and said marginal flanges and cooperating with said first named plate member to form closed refrigerant passageways around said bosses, fastening devices extending through said iianges and complementary edges of the last named plate member, similar fastening devices extending through said bosses and said last named plate member to secure the plate members together, and a header member extending along the upper edge of said plate members and in the vertical plane thereof and having a refrigerant inlet at one end and a refrigerant outlet at the other located above the passageways to retain said passageways full of refrigerant.

2. An evaporator including a plate member having a plurality of rows of spaced bosses stamped from the body portion thereof and a semi-cylindrical portion extending along its upper edge, a complementary plate member engaging said bosses and cooperating with said rst named plate member to form closed refrigerant 5 y passageways around said bosses and having a semi-cylindricalportion extending along its upper edge to cooperate with said first named senilcylindrical portion to form a header, fastening devices extending through said bosses and said 10 last named plate member to secure the plate members together, and nipples ixed in the ends of said header to form respectively a refrigerant inlet and a refrigerant outlet.

3. An evaporator including a plate member 15 having a plurality of spaced rows of bosses stamped from the body portion thereof and having outset flanges extending along the sides and bottom edges of the plate member, a complementary plate member engaging said bosses and 20 said flanges and cooperating with said rst named plate member to form closed refrigerant passageways around said bosses, fastening devices extending through said flanges and complementary edges of the last named plate member, similar fastening devices extending through said bosses and said last named plate member to` secure the plate members together, and a cylindrical header member having its axis in the plane of said plate members and extending along 30 the upper edge and having a refrigerant inlet at one end and a refrigerant outlet at the other to retain said passageways full of refrigerant and to form a direct passageway for flow of oil carried in the refrigerant. 35

4. An evaporator including a rectangularshaped plate member having a plurality of spaced vertical and horizontal rows of cylindrical bosses stamped from the body portion thereof, a at complementary plate member engaging against 40 said bosses and cooperating with said first named plate member to form closed vertical and horizontal refrigerant passageways around said bosses, fastening devices extending through said bosses and said last named plate member to 45 secure the plate members together, and a header member extending along the upper edge of said plate members and having a refrigerant inlet at one end and a refrigerant outlet at the other to retain said passageways full of refrigerant.

ALBERT E. SCHNEIDER. 

